Polystyrene multi-closure strip scored for separation into individual closures



United States Patent 3,270,874 POLYSTYRENE MULTI-CLOSURE STRIP SCOREDFOR SEPARATION INTO INDIVIDUAL CLO- SURES Frank E. Hilton, Milwaukie,Oreg., assignor, by mesne assignments, to Kwik Lok Corp., Yakima, Wash.,a corporation of Washington Filed Aug. 27, 1965, Ser. No. 483,122 2Claims. (Cl. 206-56) This invention relates to closures formed of fiatmaterial such as extruded polystyrene and, more particularly, to amulti-closure strip of such material wherein the strip is scored topermit ready detachment of individual closures.

Sheet polystyrene closures are used to close the necks of polyethylenebags in which food and other products are packaged. Such closures aremade in strip form, the strips being adapted for separation intoindividual closures. The individual closures are characterized by havinga bag-neck-con-fining mouth, which is connected to one of the edges ofthe closure by a narrow open-ing having widely flaring lips.

A problem has existed in rendering the strips separable into individualclosures. The strips are formed in a diecutting operation, and they mustfit into the various machines that have been developed to apply them tobags. Individual closures must thus be readily separable from the strip,and they must separate without leaving any sharp protrusions which mightscratch the hands of a person removing the closure from a bag. It isalso desirable that the individual closure have a cleanly formedappearance when separated from the strip, thereby to be a merchandisingasset.

-A solution to the problem was disclosed in Paxton Patent No. 3,164,250,which joined adjacent individual closures by a pair of perpendicularwebs, the length of each of the webs being substantially greater thanits width. Separation of individual closures from the strip was efiectedby in-plane forces applied perpendicular to the edges of the strip,thereby to shear the individual closures through the webs. Thisattempted solution, however, results in leaving a part or all of thewebs attached to one or the other of the adjacent individual closures,and does not effect a complete detachment of both webs at both theirends. Such, of course, results in a ragged edge appearance to theindividual closures, and leaves protrusions thereon which can scratch apersons hands.

It is thus as object of the present invention to provide a multi-closurestrip of the type above described with an improved means for separatingindividual closures therefrom.

It is a further object of the present invention to provide such amulti-closure strip with means whereby the individual closures may becompletely separated from the strip, leaving no protrusions on theirsides to scratch the hands of a person using them.

It is a still further object of the present invention to provide such amu lti-closure strip wherein the individual closures may be completelyseparated firom the strip by bending the same along axes transverse tothe strip, which axes also define the sides of adjacent individualclosures.

It is a still further object of the present invention to provide such .amulti-closure strip wherein more individual closures may be formedwithin the same length of strip, thereby to reduce wastage of material.

These and other objects are accomplished by scoring both surfaces of themulti-closure strip along axes transverse to the strip, which axesdefine the sides of adjacent individual closures, thereby to permit theindividual closures to be separated from the strip by bending the strip3,270,874 Patented Sept. 6, 1966 along the scored lines. Other objectsand advantages will be made manifest in the following description, whentaken in connection with the accompanying drawings, in which FIG. 1 is aperspective view of a preferred embodiment of the multi-closure strip ofthe present invention:

'FIG. 2 is an enlarged plan View of a portion of the strip showing ingreater detail one of the individual closures in the multi-closure stripof the present invention:

FIG. 3 is an end elevational view of the strip portion shown in FIG. 2;and

FIG. 4 is an end elevational View of an individual closure after it hasbeen completely separated from the strip.

Referring to the drawings, the preferred embodiment of the presentinvention comprises a multi-closure strip 10, which is preferably formedfrom a thin, fiat, stiff strip of polystyrene or like material, which isconventionally .035 inch in thickness and inch in width. The strip 10 isdie formed to produce in the strip a series of individual closures 11.Each individual closure 11 has a bag-neck-confining mouth 12, which isconnected to one of the edges '13 of the strip 11 by a narrow opening 14which widens into lips 15. The neck of a polyethylene bag can be twistedand inserted past the lips .15 and through the opening 14 into the mouth12 in the usual manner.

The strip -10 is formed with notches 20 in each edge 13 and notches 21in the opposite edge 22. Notches 20 and 21 are arranged symmetricallyrelative to transverse axes 23, which axes are equally spaced from andparallel to the transverse axes 24 of the bag-neck-con-fining mouths 12and openings 14. The transverse axes 23 define the sides 25 of adjacentindividual closures 11, as clearly shown in FIGS. 2 and 4. Theindividual closures 11 thus are in side-by-side relation in the strip10.

The polystyrene from which the multi-closure strip 10 is made is astilt, thin sheet material which gives the individual closures 1 1 bothstifiness and flexibility, thereby adapting them to being applied andremoved from a bag many times without injury. The polystyrene materialis also readily adapted to being scored and when so scored, is readilyfrangible along a scored line.

To permit the individual closures 11 to be separated from themulti-elosure strip 10, the strip is scored on opposite surfaces 30 and31 along lines 3-2, each of which coincides with a transverse axis 23,as clearly shown in FIGS. 2 and 3. Such scoring can be practicallyeffectuated during the die-cutting operation which forms the rest of theopenings and notches. When so scored, an individual closure 11 can becompletely broken away from the strip .10 merely by bending the closurealong the transverse axis 23, the polystyrene material readily breakingunder one or two flexures. Scoring the polystyrene to a depth of between.008 and .010 inch in each side has been found satisfactory in .035material.

The sides 25 of the separated individual closures '11 have a cleanlooking appearance and there are no protrusions that can scratch apersons hands or otherwise give the individual closure a raggedappearance. The individual closures may also be readily dispensed frommachines that apply them to the bags. Use of scoring to form the sides25 of the individual closures instead of elongated webs also results ina 5 percent saving in mate rial, since more of the individual closurescan be formed in a given length of polystyrene strip than was possibleheretofore.

While one particular embodiment of the invention has been described, itis to be understood that the specific details shown are merelyillustrative and that the invention may be carried out in other wayswithout departing from the true spirit and scope of the appended claims.

I claim:

1. In a multi-closure strip, wherein the closures has abag-neck-confining mouth and a narrow opening located in a longitudinalside edge thereof and communicating with said mouth for admitting abag-neck therein, said mouth-s and openings being symmetrical withrespect to first transverse axes across said strip,

the structure comprising:

a plurality of closures of transversely stiff, thin polystyrene, sheetmaterial arranged in side-by-side relation in said strip,

the sides of adjacent closures being defined by second transverse axeswhich are equally spaced from said first transverse axes and parallelthereto,

said strip being scored on opposite surfaces thereof along each of saidsecond transverse axes with a single continuous score extendingedge-to-edge to make said strip frangible along said second transverseaxes, said scores on each said second axes being in register,

thereby to permit individual closures to be separated from said strip bybending said strip along said second transverse axes.

2. In a multi-closure strip, wherein the closures each has abag-neck-confining mouth and a narrow opening located in a longitudinalside edge thereof and communieating with said mouth for admitting abag-neck therein, said mouths and openings being symmetrical withrespect to first transverse axes across said strip,

the structure comprising:

a plurality of closures of .035 inch thick polystyrene material arrangedin side-by-side relation in said strip,

each

the opposite edges of said strip being die cut to form notches therein,

said notches being arranged symmetrically relative to second transverseaxes which are equally spaced from said first transverse axes andparallel thereto,

said second transverse axes defining the sides of adjacent closures,

said strip being scored to a depth of between .008 and .010 inch on theopposite surfaces thereof along each of said second transverse axes witha single, continuous score extending edgeto-edge to make said stripfrangible along said second transverse axes, said scores an each saidsecond axes being in register,

thereby to permit individual closures to be separated from said strip bybending said strip along said second transverse axes.

References Cited by the Examiner UNITED STATES PATENTS 943,653 12/ 1909Coe. 2,027,343 1/1936 La Bombard. 2,636,297 4/ 1953 Johnson. 3,164,2501/1965 Paxton 206-56 FOREIGN PATENTS 1,276,833 10/ 1961 France. 596,3117/1959 Italy.

THERON E. CONDON, Primary Examiner.

J. M. CASKIE, Assistant Examiner.

2. IN A MULTI-CLOSURE STRIP, WHEREIN THE CLOSURES EACH HAS ABAG-NECK-CONFINING MOUTH AND A NARROW OPENING LOCATED IN A LONGITUDINALSIDE EDGE THEREOF AND COMMUNICATING WITH SAID MOUTH FOR ADMITTING ABAG-NECK THEREIN, SAID MOUTHS AND OPENINGS BEING SYMMETRICAL WITHRESPECT TO SAID TRANSVERSE AXES ACROSS SAID STRIP, THE STRUCTURECOMPRISING: A PLURALITY OF CLOSURES OF .035 INCH THICK POLYSTYRENEMATERIAL ARRANGED IN SIDE-BY-SIDE RELATION IN SAID STRIP, THE OPPOSITEEDGES OF SAID STRIP BEING DIE CUT TO FORM NOTCHES THEREIN, SAID NOTCHESBEING ARRANGED SYMMETRICALLY RELATIVE TO SECOND TRANSVERSE AXES WHICHARE EQUALLY SPACED FROM SAID FIRST TRANSVERSE AXES AND PARALLEL THERETO,SAID SECOND TRANSVERSE AXES DEFINING THE SIDES OF ADJACENT CLOSURES,SAID STRIP BEING SCORED TO A DEPTH OF BETWEEN .008 AND .010 INCH ON THEOPPOSITE SURFACES THEREOF ALONG EACH OF SAID SECOND TRANSVERSE AXES WITHA SINGLE, CONTINUOUS SCORE EXTENDING EDGE-TO-EDGE TO MAKE SAID STRIPFRANGIBLE ALONG SAID SECOND TRANSVERSE AXES, SAID SCORES AN EACH SAIDSECOND AXES BEING IN REGISTER, THEREBY TO PERMIT INDIVIDUAL CLOSURES TOBE SEPARATED FROM SAID STRIP BY BENDING SAID STRIP ALONG SAID SECONDTRANSVERSE AXES.